In the circuit and system theory and in practice it is of interest to minimize an impedance of interest. Further in order to achieve mathematically complete, and thus ideal, load independent operation, it can be shown that an impedance of interest should be forced to zero. All known techniques produce less or more successful minimization of the impedance of interest, usually in proportion to their complexity. None of the presently known techniques produces a zero impedance, except synthesis methods described in copending and coassigned applications by these two same inventors Lj. Dj. Varga and N. A. Losic, "Synthesis of Zero-Impedance Converter", Ser. Nr. 07/452,000, December 1989, N. A. Losic and Lj. Dj. Varga, "Synthesis of Improved Zero-Impedance Converter", Ser. Nr. 07/457,158, December 1989, allowed for Issuance June 1990, N. A. Losic and Lj. Dj. Varga, "Parameter-Free Synthesis of Zero-Impedance Converter", Ser. Nr. 07/484,494, February 1990, and N. A. Losic and Lj. Dj. Varga, "Current-Free Synthesis of Parameter-Free Zero-Impedance Converter", Ser. Nr. 07/503,229, April 1990. A specific and particular applications of a zero-impedance converter, in addition to those in the applications above, are described in the U.S. Pat. No. 4,885,674 "Synthesis of Load-Independent Switch-Mode Power Converters" by Lj. Dj. Varga and N. A. Losic, December 1989, as well as in two copending and coassigned applications of N. A. Losic and Lj. Dj. Varga, "Synthesis of Load-Independent DC Drive System", Ser. Nr. 07/323,630, November 1988, and "Synthesis of Load-Independent AC Drive Systems", Ser. Nr. 07/316,664, February 1989, allowed for Issuance December 1989.
Another advantage due to the use of the zero-impedance converter, seen in creating possibility to reduce order of an electric motor drive system to zero by implementing appropriate (feed) forward algorithms in addition to realizing the zero-impedance converter to produce a load independent operation, is explored and described in a copending application Ser. No. 07/468,122 by N. A. Losic and Lj. Dj. Varga "Synthesis of Drive Systems of Infinite Disturbance Rejection Ratio and Zero-Order Dynamics/Instantaneous Response", January 1990. Furthermore, a generalized synthesis method to produce zero order dynamics, i.e., instantaneous response, and infinite disturbance rejection ratio in a general case of control systems of n-th order is described in a copending and coassigned application by Lj. Dj. Varga and N. A. Losic, "Generalized Synthesis of Control Systems of Zero-Order/Instantaneous Response and Infinite Disturbance Rejection Ratio", Ser. Nr. 07/479,275, February 1990.
The zero impedance converter and its particular and specific applications, as described in the patents/patent applications on behalf of these two inventors listed above, except the patent application Ser. No. 07/484,494 and patent application Ser. No. 07/503,229, operate on specific (given) values of resistive and reactive parts of an impedance of interest. In the Application No. 07/484,494, a parameter-free algorithm is based on current and voltage measurements in real time. A current-free synthesis method of a parameter-free zero-impedance converter, whereby no current is measured and processed and no parameters of the impedance of interest are needed to be known, is disclosed in application Ser. No. 07/503,229.